This invention relates to an intermediate moisture pet food which forms a gravy mixture upon the addition of a warm, aqueous liquid.
Intermediate moisture pet foods generally are classified as having a moisture level between about 15-55% with added antimicrobial materials to stablize and preserve the product during storage. This type of product has had increased acceptance in the pet food market as an alternative to the dry pet food products. While the latter offer the advantage of convenience and a long shelf life, the soft moist products generally are considered to be more palatable because of the higher moisture level. Typical soft moist products and methods for their production are described in U.S. Pat. Nos. 3,852,483; 3,202,514; 3,615,652; 3,653,908; 3,482,985; 3,745,021; 4,011,345 and 4,011,346. All of these represent variations in the materials or means of stabilizing the product and preserving it at ambient conditions over a period of time. Typical moisture levels for products produced in the above patents are between 15 and 55% by weight.
One means of improving the acceptability and palatability of dry pet foods has been to add a dry gravy forming material to the surfaces of the dry pet food. The presence of the material on the dry product presents no storage problems and when the consumer adds an aqueous liquid to the dry product a gravy-like mixture is formed. Typical products of this type are described in U.S. Pat. Nos. 3,119,691; 3,467,525; 4,104,407 and 4,104,406. The gravy forming materials disclosed in the above references generally can be pregelatinized starches, gums, or various other polysaccharides or thickeners. As described in U.S. Pat. No. 3,119,691 these gravy forming ingredients are usually applied to the dried expanded pellet immediately following or together with a fat that is sprayed on the surface of the expanded material. The fat forms a coating on the pet food, and the particles of gravy forming material become available on the surface of the fat coated pellet to quickly form a gravy when an aqueous liquid makes contact with the particles. U.S. Pat. No. 3,467,525 describes a somewhat different process for a gravy forming, dry pet food by a two-stream process in which a portion of the pellets are coated with fat which are then heated to promote fat penetration followed by coating of a separate portion of the pellets with a thickener. The combined mix of pellets provides a thickened mixture upon the addition of an aqueous liquid. U.S. Pat. No. 4,104,406 describes a dry expanded pet food which is first coated with a fat/dextrin emulsion to resist hydration of the expanded particle followed by coating with gravy forming materials. This product is also characterized by the presence of gravy forming materials on the outer surface to provide immediate thickening upon addition of an aqueous liquid. U.S. Pat. No. 4,104,407 is similar except that separate layers of fat and dextrin are provided to prevent extensive hydration of the expanded particle when the gravy is formed.
Intermediate moisture pet foods would likewise have increased appeal to the consumer if a gravy-like mixture could be formed with the pet food upon the addition of an aqueous liquid. Conceptually, an intermediate moisture product with a gravy forming material on the surfaces thereof is difficult to obtain since the gravy forming materials react quickly with any moisture to form a gravy and the presence of 15-55% inherent moisture in a soft moist pet food could activate any thickener applied to the product during storage. This premature activation by the moisture in this type of product makes the addition of a gravy former a difficult task, since the ultimate objective is to produce a product which will retain its appearance during storage but will form a gravy-like mixture only when water has been added by the consumer.
This problem has been overcome in the present invention and accordingly it is an object of the present invention to produce an intermediate moisture pet food which will form a gravy-like mixture upon the addition of an aqueous liquid.
It is also an object of the present invention to produce a gravy forming intermediate moisture pet food that will avoid activation of the gravy forming components by the inherent moisture in the pet food product.
It is a further object to produce a gravy forming intermediate moisture pet food that will retain its gravy forming characteristics during storage without activation by the inherent moisture present in the pet food product.
It is an object to provide an intermediate moisture pet food which will form a gravy-like mixture upon the addition of an aqueous liquid which will be of increased appeal and acceptability to both the consumer and the pet.